 # ML Aggarwal Solutions Class 10 Mathematics Solutions for Mensuration Exercise 17.4 in Chapter 17 - Mensuration

A toy is in the form of a cone of radius 3.5 cm mounted on a hemisphere of same radius. If the total height of the toy is 15.5 cm, find the total surface area of the toy.

Solution:

The given toy is the combination of cone and hemisphere so we need to add the curved surface area of both to get the total surface area of the toy. Given radius of the cone, r = 3.5 cm

Radius of hemisphere, r = 3.5 cm

Total height of the toy = 15.5 cm

Height of the cone = 15.5 – 3.5 = 12 cm

Slant height of the cone, l = √(h2+r2)

l = √(122+3.52)

l = √(144+12.25)

l = √(156.25)

l = 12.5 cm

Total surface area of the toy = curved surface area of cone + curved surface area of the hemisphere

= π rl + 2π r2

= π r(_l+_2r)

= (22/7)×3.5×(12.5+2×3.5)

= (77/7)×(12.5+7)

= 11×19.5

= 214.5 cm2

Hence the total surface area of the toy is 214.5 cm2.

Related Questions

Lido

Courses

Teachers

Book a Demo with us

Syllabus

Maths
CBSE
Maths
ICSE
Science
CBSE

Science
ICSE
English
CBSE
English
ICSE
Coding

Terms & Policies

Selina Question Bank

Maths
Physics
Biology

Allied Question Bank

Chemistry
Connect with us on social media!